107 years ago today, on May 16, 1918 (April 7, 1918 lunar calendar), Duan Qirui and Japan signed the "Sino-Japanese Army Joint Anti-Enemy Military Agreement". On May 16, 1918, the Japanese Army Major General Kidjiro Saito and Duan Qirui's government representative Jin Yunpeng secretly signed the "Sino-Japanese Army Joint Anti-Enemy Military Agreement" in Beijing. On the 19th, the "Sino-Japanese Navy Joint Anti-Enemy Military Agreement" was signed. The so-called "enemy defense" refers to Soviet Russia after the October Revolution. At that time, international imperialist armed forces intervened in the Russian Revolution. Japan attempted to take the opportunity to invade Russia and monopolize Northeast China. " The main contents of the "agreement" are: China and Japan take "joint defense against the enemy" actions; Japan can enter China during the war; when the Japanese army is fighting outside China, China should send troops to support; during the war, the two countries supply each other with weapons and munitions. Through the "agreement", Japan sent a large number of troops into Northeast China, and Japan quickly replaced the aggressive position of Tsarist Russia in the northern three northeastern provinces. China faces the danger of being exclusively occupied by Japan as a vassal state. Peng Pai, a student studying in Japan, marched in Tokyo to protest, and then withdrew from school and returned to China. He organized national rescue groups and carried out patriotic propaganda in various places. More than 2,000 students from Peking University and other schools went to the presidential palace to demand the abrogation of the contract. Students from Tianjin, Shanghai, Fuzhou and other places also rose up to demand the abrogation of the contract. Workers and businesspeople across the country have also accused the Duan Qirui government of betraying the country.